Linked Life Data

10712249

Source:http://linkedlifedata.com/resource/pubmed/id/10712249

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2000-9-22
pubmed:abstractText
Inorganic phosphate (P(i)) accumulates in the fibers of actively working muscle where it acts at various sites to modulate contraction. To characterize the role of P(i) as a regulator of the sarcoplasmic reticulum (SR) calcium (Ca(2+)) release channel, we examined the action of P(i) on purified SR Ca(2+) release channels, isolated SR vesicles, and skinned skeletal muscle fibers. In single channel studies, addition of P(i) to the cis chamber increased single channel open probability (P(o); 0.079 +/- 0.020 in 0 P(i), 0. 157 +/- 0.034 in 20 mM P(i)) by decreasing mean channel closed time; mean channel open times were unaffected. In contrast, the ATP analog, beta,gamma-methyleneadenosine 5'-triphosphate (AMP-PCP), enhanced P(o) by increasing single channel open time and decreasing channel closed time. P(i) stimulation of [(3)H]ryanodine binding by SR vesicles was similar at all concentrations of AMP-PCP, suggesting P(i) and adenine nucleotides act via independent sites. In skinned muscle fibers, 40 mM P(i) enhanced Ca(2+)-induced Ca(2+) release, suggesting an in situ stimulation of the release channel by high concentrations of P(i). Our results support the hypothesis that P(i) may be an important endogenous modulator of the skeletal muscle SR Ca(2+) release channel under fatiguing conditions in vivo, acting via a mechanism distinct from adenine nucleotides.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0363-6143
pubmed:author
pubmed:issnType
Print
pubmed:volume
278
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C601-11
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Mechanisms of P(i) regulation of the skeletal muscle SR Ca(2+) release channel.
pubmed:affiliation
Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, St. Paul, Minnesota 55455, USA. balog004@tc.umn.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't